The field of the disclosure relates generally to railroad grade crossings, and more specifically, to methods and systems for detection and notification of blocked rail crossings.
Train traffic in North America typically intersects with public streets and highways at railroad grade crossings. At such crossings, active and/or passive warning systems provide a notification to automotive traffic regarding the impending arrival of a train. The particular notifications provided are somewhat dependent on the street or highway intersecting the rail line. For example, where average train speeds or automotive traffic volume warrants, active warning systems are deployed which may include one or more of flashing lights, bells, and barrier gates. As high speed rail infrastructure is expanded to promote high-speed intercity passenger service, more attention is being paid to the performance of these warning systems.
While the active warning systems are effective, risks persist. One such risk is that associated with the instance of vehicles that are found within the crossing island, which is the area between barrier gates where the rails are located. Such vehicles may be accidently or deliberately placed in such crossing islands. For example, a vehicle may become disabled while within or near the crossing island. Instances have occurred where automobile drivers have driven around the barrier gates only to find themselves trapped within the crossing island. Instances have also occurred wherein motorists have also mistakenly driven their vehicles outside the crossing island and the Minimum Track Clearance Distance (MTCD) area or zone and onto the railroad tracks, with the vehicles becoming temporarily stuck on the tracks in the path of a potential approaching train. As presently defined in defined in the Manual on Uniform Traffic Control Devices (MUTCD), the minimum track clearance distance is the length along a highway at one or more railroad tracks, measured either from the railroad stop line, warning device or 3.7 m (12 ft) perpendicular to the track centerline to 1.8 m (6 ft) beyond the track(s) measured perpendicular to the far rail, along the centerline or edge line of the highway, as appropriate, to obtain the longer distance.
High mass freight trains, at speeds of 55 miles per hour and greater take thousands of meters to halt, a situation that becomes more perilous with a current emphasis on development of high-speed rail traffic (80-110 MPH (grade separation is required above 110 MPH)). At such speeds, locomotive operators and engineers have insufficient time to halt the train if such an obstruction is visually identified at or near an upcoming crossing.
Currently, railroad companies seek to provide advance warning of track obstruction situations by posting a toll free telephone number on the equipment bungalow near the crossing islands, implicitly encouraging the general public to place a telephone call if a dangerous situation has developed at or near a crossing island. Should a member of the public make the call, the railroad operator will forward the information to locomotive engineers in the vicinity. It is apparent, however, that a more reliable, deterministic means of identifying these risks and communicating actionable information to railroad organizations would be an improvement over current reporting mechanisms.